Perl is a popular scripting language that's designed to make various web-oriented applications, which includes CGI scripts. Among the attributes that distinguish it from other languages is the usage of modules - batches of Perl program code that do predefined tasks and they are universally accepted. In simple terms, instead of generating custom-made program code to perform something or pasting tens and hundreds of lines of program code in your script, you will be able to "call" some module which is already available for this specific process and use only a couple of lines of code. Consequently, your script shall be executed more rapidly as it is much smaller. Using modules will additionally make the script much easier to modify considering that you will have to go through a smaller amount of program code. In case you'd like to use Perl on your site, you should ensure that the mandatory modules are present on the server.